i have recently floored my loft in december 2012 and have noticed white mould has formed on the roof of the loft etc.the flooring was left a good 6 inch+ away from the eves on both sides and i have taken up the edge cuts of chipboard to allow more air circulation to rise from the eves since i first noticed the mould growth.i have also left the window slightly open to provide an adaquate amount of air untill i get vents fitted.the skylight window was always condensated and since i have started to leave it open the condensation has gone.the mould only started after the chipboard was layed obviously preventing the air from rising from the eves above the floor but not sure if the eves will ventilate the whole loft now flooring is layed. i have wiped most of the mould off with a cloth and mould killer spray but have been told by builders that it will need to be sprayed professionally in order to kill the mould completely......could anyone inform me if this would be necessary? with regards to getting vents fitted i have a gable end wall at the far side of the loft as well as a small room in the loft which also has an exterior wall.the small room had more mould growth because there is less ventilation and was thinkin of putting two vents on gable end wall and one in the other wall in the small room in loft.could anyone inform me what type of vents should i get fitted wall vents or roof vents through the roof slates and can both be done or just one way or the other ie wall or roof or both? shouldve got the vents fitted before floor was laid but windows acting as a vent in the meantime.....any advice would be truly appreciated!!